The Daily Review/Bill Decker
Rising water isn't a problem if you're a great blue heron, top photo, or a cormorant, bottom, both of which were fishing Thursday on the Berwick waterfront. But representatives of the human species are taking precautions against a projected 7.5 feet crest on the Atchafalaya River later this month.

Officials: Bayou Chene closure not expected

As St. Mary Parish officials begin to prepare for an anticipated 7.5-foot crest in the Atchafalaya River, there are no plans to block Bayou Chene in Amelia as has been done in the past to prevent backwater flooding in the region.

The Atchafalaya topped the 6-foot flood stage Thursday and was at 6.03 feet as of 6 a.m. Friday, according to the National Weather Service. The river is expected to be in the 6-foot to 6.1-foot range through Wednesday.

Morgan City officials planned to close floodgates Friday along the riverfront at Freret Street and Railroad Avenue. Berwick leaders were planning to close a floodgate at First Street. The decision for additional gate closures had not yet been made as of Thursday afternoon.

The St. Mary Levee District Commission also met Thursday at the parish courthouse.

The Atchafalaya River is projected to crest at 7.5 feet in Morgan City on March 24, Levee District Executive Director Tim Matte said. The river crested at 7.2 feet in 2017 and at 8.2 feet in 2016.

That crest shouldn’t cause any major problems for St. Mary Parish, and officials do not have any plans yet to install a temporary flood protection structure on Bayou Chene, Matte said.

The levee district installed a temporary barge on Bayou Chene in 2016 to block potential flood waters. Officials decided to block Bayou Chene that year, in part, due to a projected 9.5-foot crest with the potential opening of the Morganza Spillway.

That 2016 closure cost nearly $7 million, but the federal government reimbursed the levee district for 75 percent of that cost because of a federal emergency declaration.

Eventually, officials plan to install a permanent floodgate on Bayou Chene, but construction isn’t expected to begin on that project until April 2020.

On Thursday, the U.S. Army Corps of Engineers opened the Bonnet Carre Spillway to divert flood waters.

“There’s a limit to how much flow they can put through that structure,” Matte said. “If they get to the point where they’ve opened the entirety of the Bonnet Carre and they still have a need to flow more water, then that does put pressure on the Atchafalaya side.”

No decision has been made to open the Morganza Spillway, which hasn’t been opened since 2011.

Predictions for the water level at the confluence of the Mississippi and Ohio rivers in Cairo, Illinois, “indicate some relief coming,” Matte said. And then within the next four weeks the Atchafalaya region should begin to see relief in terms of dropping river levels, he said. Rainfall throughout the entire Ohio Valley typically contributes to Atchafalaya River levels, too.

With that anticipated crest, levee district officials have started preparing for the high water by identifying any vulnerable areas in the parish. Officials slightly raised a 200-foot long section of lower levees near Walnut Street Canal, Matte said. District leaders also took survey data in Amelia, but there shouldn’t be any big issues there based on the projected crest, he said.

St. Mary Levee District personnel recently met with officials in Terrebonne Parish to discuss concerns that Terrebonne leaders had about the river crest and whether to close Bayou Chene.

Workers have already raised many of the levees in the Morgan City area as part of a levee improvement project. Therefore, if the high water does cause any problems in Amelia, “flood fighting in Amelia might be a cheaper alternative and equally effective alternative for the St. Mary residents” instead of closing Bayou Chene, Matte said. Flood fighting could entail measures such as placing Hesco baskets filled with sand to protect certain areas from flooding.

In discussion with Terrebonne Parish officials, St. Mary Levee District officials expressed willingness to manage a temporary closure of Bayou Chene, if that closure was deemed necessary.

But funding to close Bayou Chene would have to come from Terrebonne and other parishes, Matte said. Terrebonne officials accepted that condition should they decide that closing Bayou Chene is in Terrebonne’s best interest and agreed to get other parishes on board to help fund any possible temporary Bayou Chene project, he said.

If such a closure takes place, the St. Mary Levee District and entities in surrounding parishes would first have to sign a cooperative endeavor agreement.

“We’ve told other parishes what we told Terrebonne Parish, that we’re not going to participate other than to be the facilitator,” St. Mary Levee District Commission President Bill Hidalgo said.

A significant area of Terrebonne Parish, including many homes and businesses, is affected when flood waters travel through Bayou Chene, Hidalgo said.

In other business, the commission

—Approved an agreement with Morgan City Harbor and Terminal District for the use of conference and training rooms.

—Approved a resolution to close and gate the levee haul road from Charenton Beach Road to Myette Point, except access to public boat launches.

—Approved an agreement with K/D/S Promix LLC pipeline company for levee repairs in the Berwick area.

—Approved purchase of a front end loader attachment to aid in levee maintenance and amended an agreement with St. Mary Parish government.